Mesa and Garfield Counties Colorado, and Grand San JuanWayne and
<br />Garfield Counties, Utah. The Colorado River and its 100-year floodplain from
<br />the Colorado River Bridge at exit 90 north off Interstate 70 in T. 6 S., R. 93 W.,
<br />section 16 (6th Principal Meridian) to North Wash, including the Dirty Devil arm
<br />of Lake Powell up to the full pool elevation, in T. 33 S., R. 14 E., section 29 (Salt
<br />Lake Meridian).
<br />San Juan County. New Mexico; and San Juan County, Utah. The San Juan River
<br />and its 100-year floodplain from the State Route 371 Bridge in T. 29 N.,
<br />R. 13 W., section 17 (New Mexico Meridian) to Neskahai Canyon in the San Juan
<br />arm of Lake Powell in T. 41 S., R. 11 E., section 26 (Salt Lake Meridian) up to
<br />the full pool elevation.
<br />The final critical habitat rule identified water, physical habitat, and the biological
<br />environment as the Primary Constituent Elements (PCEs) of critical habitat. The water
<br />PCE was further described as including a quantity of water of sufficient quality (i.e.,
<br />temperature, dissolved oxygen, lack of contaminants, nutrients, turbidity, etc.) that is
<br />delivered to a specific location in accordance with a hydrologic regime that is required
<br />for the particular life stage for each species. The physical habitat includes areas of the
<br />Colorado River system that are inhabited or potentially habitable by fish for use in
<br />spawning, nursery, feeding, and rearing, or serve as corridors between these areas. In
<br />addition to river channels, these areas also include bottom lands, side channels, secondary
<br />channels, oxbows, backwaters, and other areas in the 100-year floodplain, which when
<br />inundated provide access to spawning, nursery, feeding, and rearing habitats. The
<br />biological environment PCE includes food supply predation, and competition. Food
<br />supply is a function of nutrient supply, productivity, and availability to each life stage of
<br />the species. Predation and competition, although considered normal components of this
<br />environment, are out of balance due to introduced nonnative fish species in many areas.
<br />Species/Critical Habitat Likely to be Affected
<br />The Colorado pikeminnow and its critical habitat in the action area are likely to be
<br />adversely affected. The area of critical habitat likely to be affected is, the Colorado River
<br />at the confluence with Salt Creek in T. 9 S., R. 103 W., section 33 (Ute Meridian),
<br />continuing down from this point of the Colorado River and its 100-year floodplain to
<br />North Wash, and the Dirty Devil arm of Lake Powell up to the full pool elevation, in
<br />T. 33 S., R. 14 E., section 29 (Salt Lake Meridian).
<br />Analysis of Species/Critical Habitat Likely to be Affected
<br />The Grand Valley area is occupied year round by Colorado pikeminnow and has been
<br />identified as important habitat. The densities of adult Colorado pikeminnow are
<br />especially high in the Colorado River in the Grand Valley (Figure 1). The Colorado
<br />River in the Grand Valley is divided into two reaches: the 15-mile reach (above the
<br />confluence of the Gunnison River) and the 18-mile reach (below the confluence of the
<br />Gunnison River) shown as stratum 8 and 9 in Figure 1. The proposed project site is just
<br />below the 18-mile reach.
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